#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) != EOF)
    {
        if ((a + b > c) && (a + c > b) && (b + c > a))
        {
            if ((a == b) && (a == c))
            {
                printf("Equilateral triangle!\n");
            }
            else if ((a == b) || (a == c) || (b == c))
            {
                printf("Isosceles triangle!\n");
            }
            else {
                printf("Ordinary triangle!\n");
            }
        }
        else {
            printf("Not a triangle!");
        }
    }
    return 0;
}